[Ascariasis is a zoonosis in Denmark--secondary publication]

It has been claimed that Danish cases of human ascariasis have been acquired either during travel to other countries or through consumption of untreated food imported from areas where human ascariasis is endemic. An epidemiological survey in Viborg County indicated, however, that pigs are the primary source of the infection. Our population-genetic investigations have now confirmed this hypothesis. The main transmission route for human ascariasis in developed countries therefore seems to be from pigs to people; thus, it is essential that contact with pig manure be avoided, especially by young children.